Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 110, NWS Great Falls, MT

August 10, 2002Blaine County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 10, 2002, 9:55 PM MDT for Blaine County, Montana. It was in force for 20 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 10, 2002, 9:55 PM MDT (03:55 UTC)
Expired: Aug 10, 2002, 10:15 PM MDT
In force: 20 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Blaine County, MT

The radar

The Glasgow radar (KGGW), 144 km from the middle of the area, began a volume at 03:54 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 3.9 hours before the alert went out and 145 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 88 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 2460 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 14 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

903 
WUUS55 KTFX 110355
SVRTFX
MTC005-110415-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
953 PM MDT SAT AUG 10 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL BLAINE COUNTY IN NORTH CENTRAL MONTANA

* UNTIL 1015 PM MDT

* AT 950 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
  SEVERE THUNDERSTORM OVER EAST CENTRAL BLAINE COUNTY...OR ABOUT 31  
  MILES EAST OF CHINOOK...MOVING EAST AT 35 MPH.

THIS STORM MAY PRODUCE HAIL UP TO ONE INCH IN DIAMETER...WIND GUSTS 
TO 60 MPH...AND BRIEF HEAVY RAINFALL OF UP TO THREE TENTHS OF AN 
INCH IN 20 MINUTES.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

LAT...LON 4867 10854 4843 10859 4841 10843 4874 10833

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 10, 8:50 PM MDT, 1 hour 5 minutes earlier.

Area forecast discussion, Aug 10, 8:50 PM MDT, 1 hour 5 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
850 PM MDT SAT AUG 10 2002

.SHORT TERM...WILL UPDATE ZONES FOR WORDING. APPEARS THAT THE COLD
FRONT HAS GONE THROUGH CUT BANK. WINDS GUSTY BEHIND FRONT AND
CURRENT FORECAST HANDLES WINDS WELL. THUNDERSTORMS MOVING SOUTH INTO
CWA FROM CANADA ARE HOLDING TOGETHER WELL. HAVE HAD REPORTS OF
BRIEF HEAVY RAINS AND HAIL FROM 1/2 TO OVER ONE INCH. CAMP

.EXTENDED...DRY NW FLOW ALOFT THROUGH PERIOD WITH A SHORT WAVE/COLD
FRONT TO MOVE THROUGH ON WEDNESDAY. WILL MENTION A SLIGHT CHANCE OF
SHOWERS FOR WEDNESDAY. TEMPERATURES SHOULD STAY COOLER THAN NORMAL.
FLOW BEGINS TO BECOME SW AND PICKING UP SOME MOISTURE BY NEXT
WEEKEND.  CAMP

.CCF NUMBERS
GTF EE 052/068 045/074 048 13121
    BEBBB 080/048 078/050 078/048 075/048 075 11112111111
CTB CE 049/065 043/070 046 13331
    BBBBB 076/048 076/045 078/048 074/048 074 11112111111
HLN EB 050/072 046/078 050 13121
    BBBBB 082/048 083/051 081/050 078/050 078 11112111111
BZN EB 044/074 040/076 040 13011
    BBBBB 078/046 080/047 078/045 079/047 076 11111111111
WEY EB 035/065 033/070 035 13011
    BBBBB 072/043 075/045 075/045 072/045 072 11111111111
DLN EB 047/074 042/073 042 13011
    BBBBB 075/048 080/050 080/047 078/047 078 11111111111
HVR WB 054/068 045/075 050 13331
    BBBBB 082/048 078/050 080/048 077/047 076 11112111111
LWT WB 047/067 042/070 045 13121
    BBBBB 075/046 077/048 078/050 075/047 073 11112111111

.TFX...NONE.

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 10, 7:52 PM MDT	Severe Thunderstorm Warning	TFX	Hill	38 min
Aug 10, 8:32 PM MDT	Severe Thunderstorm Warning	TFX	Hill	28 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002 Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.